<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
    <script src="https://cdn.jsdelivr.net/npm/vue@2.6.10/dist/vue.js"></script>
  </head>
  <body>
    <div id="app">
      <div>
        <!-- 
          .lazy修饰符:
            把v-model的本质中@input事件改变为@change事件
            当input失去焦点的时候才会触发更新数据

          .trim修饰符 
            取掉收集的数据的前后空白字符
         -->
        <input type="text" v-model.lazy.trim="msg" />
        {{msg}}
        <hr />
        <div>
          <!-- 
            .number修饰符是在v-model收集表单数据时,把收集的数据转为number类型
            转换的标准是:类似于parseFloat,但是如果遇到无法转换的,则直接收集为字符串了
           -->
          <input type="text" v-model.number="count" />
          {{count}}
        </div>
      </div>
    </div>
    <script>
      const vm = new Vue({
        el: "#app",
        data() {
          return {
            msg: "",
            count: 0,
          };
        },
      });
    </script>
  </body>
</html>